BP/MUSTANG - HOLSTEIN TRUSS SPAR

Gulf of Mexico, USA

Platform

BP’s Holstein platform has a truss SPAR substructure with an integrated topsides structure. The platform location is the Gulf of Mexico in a water depth of 1324m.

Challenge

As part of Mustang’s detail design of the substructure, MSL was commissioned to undertake a study to achieve an improved understanding of the response of the structure to fire loading in order to optimize the requirement for, and location of, passive fire protection. This study was required to be carried out within a tight field development schedule.

MSL Scope

MSL’s scope of activities were sub-divided into three Phases:

• Phase 1 involved the collation of necessary data and the establishment and agreement of all relevant loading, response and survival criteria. 

• Phase 2 involved a thermal analysis and design-level structural redundancy analysis of the structure to identify passive fire protection requirements. 

• Phase 3 included a progressive collapse analysis of the structure, using the industry standard USFOS software, under fire loading to further optimize the requirements for fire protection.

The fire scenarios included both pool and jet fires.

Benefits

The scope was carried out within the stringent project timescale, and the optimization studies and assessment delivered cost benefits from reduced material and installation costs combined with improved fabrication efficiency through avoidance of the need for costly in-module passive fire protection repairs and reinstatement.